Tuesday / Wednesday Storm (Monday Afternoon Update)

I am actually quite impressed with this storm, and we are still 18 hours from go time. Models have been very consistent with this storm, so confidence is pretty high with this one. One thing that has been showing up on the models once again today is the effects of the banding that will setup. To illustrate that, here are two models depicting banding. Now, where exactly they set up will be the mystery. I am also very confident they will setup across NJ. The first model here is the RGEM model (Canada) showing a band setting up across central areas of NJ (yellow stripe). 

The second is the NAM (American)  model. Now, this is a 1 hour shot of a potential band (yes, that's 3.5" per hour) in the speck in Monmouth / Ocean County. Other areas are still very significant 1 hour rates:

So, as you can see, we are dealing with a VERY potent system. Models have been depicting over and over again for about .5-.75" inches water over the area, so that would translate to a good snowfall of 6-10" With that, I am raising my expected accumulations to 6-10" as a base. I am also going to say, if you get stuck under a band, you will be looking at 8-12" of snow. I even think there could be some areas along coastal sections of NJ (Monmouth Ocean Counties) that could go over 12" of snow. With winds gusting as well in the 20mph range, blowing snow will be a concern. I also think there will be locations reporting thundersnow tomorrow evening into the night as the low pressure really bombs out in the Atlantic. 

I will also preface this by saying, when we have strong lifting creating bands of snow, there will be other areas that will have very light precipitation. So, I think there will be a sharp cutoff to areas in NW NJ and NE PA. I truly believe this will be a I-95 special from DC to Boston. 

As always, updates will be coming on facebook and twitter. I will post a blog posting after the nightime model runs as well. 

All In..... Here We Go!

I have been talking over the past couple of days about it all coming down to the phasing. Well, it does. And, what the models have been showing today is an earlier phase, creating a colder solution, more intense storm, and more precipitation. While there is more precipitation, it doesn't mean we escape rain free everywhere. Many areas in Central NJ will wake up to snow tomorrow that will change to rain. Don't fret, this is an overrunning event from the southern low pressure. Although it changes to rain, it will change back to snow during the afternoon hours. This will be due to the phase of the southern and northern storms. The northern storm will be bringing the cold air to the party. Tomorrow night may be pretty wild even down into Philly.

After seeing two bombs on the NAM model, the Euro holding serve, GFS still showing moderate snows and the SREF models trending colder with identical precipitation amounts, its time. Time to go all in and up some amounts. 

From Allentown, PA to Newark (Rt 78) and NYC north, this will be an all snow event. areas south of there will start as snow, go over to a mix and rain, and then back to snow. Tomorrow night will produce heavy snows, possible thundersnow and snowfall rates of up to an inch an hour. A lot of that will be nowcasted, which I will post on twitter and facebook. 

SNOWFALL AMOUNTS:

Philly south to NE MD: 1-3"

Philly North to 195 3-6" 

195 North to 78 6-10" 

78- NYC 10-12" 

Lower Hudson Valley - RT 91 in CT 12-20" 

RT 91 to East Coast 20-30"

these are my conservative numbers now. Pretty confident throwing these out there. 

follow laong on twitter and facebook tomorrow for up to the minute updates and things to keep an eye on.

Stay Safe

Oh- and a special shout out to Rose and Susan from BEI, thanks for following!

New England Historic Storm Taking Shape

If there is one thing that is pretty certain here, is that New England is going to get smoked. These estimates of 24-30" of snow are realistic. This is going to be an old fashioned, New England blizzard. For the rest of us, from NYC south, the uncertainty remains king. We are dealing with two separate low pressures. One, a disturbance diving out of Canada towards the East Coast. The other, a low pressure in the Gulf States. These two low pressures will phase, or merge, along the East Coast and move ENE around the "benchmark"

EDIT- I have mentioned the "benchmark" on several posts, but I have probably not done a good job explaining why this is important. The "benchmark" is located at 40N and 70W and the significance is that a large majority of winter storms pass over this area bringing the perfect balance of distance to bring the biggest storms.

So, the questions remain where exactly these two low pressures phase, how phased the evolving storm can intensify, speed of travel and track of the storm. Each model is still showing some different outcomes based on these variables. Each model is also able to pick up on subtle characteristics that are making the forecast very difficult. Overnight, the NAM model had zero snow for Philly. The GFS showed a couple inches for Philly and the Euro was like 6" for Philly. Whats more mind boggling is while Boston is looking at 30", NYC could very well hit 12" of snow, while Philly sits at zero. This is the type of spread we have. Any earlier phase, we could be looking at substantial snows. Any later, or a further east track, we will be looking at showers with next to nothing.

For now, I am going with snow starting very early tomorrow morning (5- 7 am). Late morning we switch to mixed precipitation and rain. Late afternoon we switch back to snow and may get some period of moderate snows. I think from 195 north to NYC, 3-6" can be expected while areas from 195 south to Philly can expect 1-3". This is based on my current thoughts, but confidence is still low on this. By tonight I will issue a final. Places in NW NJ and the Lower Hudson Valley 8-12" can be expected while areas to the east from I87 - I91  12-20" and then from I91-East Coast 20-30".

Please remember for those areas looking to get walloped that this will be a rapidly intensifying storm and the winds will be whipping. There is also a higher than normal chance for thundersnow. Snowfall rates will easily make 1-3"/hour in many locations, if not more. This will be a very intense and dangerous storm.

Wednesday Morning Update For Friday

As mentioned yesterday, the EURO model has been very very consistent with a significant East Coast storm for a number of successive runs now. This has continued. Not only has it continued, but every run seems to signify a bigger storm. By bigger, I mean affecting more areas. yesterdays midday run was a huge run for areas in New England. As I wrote yesterday, the low pressure was centered off the Carolina coast and moved to the "benchmark" and really hammered New England (specifically the Boston to Maine area). This track and intensity was a bit too late for areas south of NYC.

Last nights overnight EURO run actually shows a low pressure taking shape at the NC/SC border. From here it moves up and rapidly strengthens and brings measurable snowfall into the Philadelphia - NYC corridor. So, this will actually have to be watched to see if this continues. The GFS model did not even show this type of setup 1.5 days ago, but has really trended towards the EURO model. For now, the GFS keeps this as a New England event, with some rain changing over to snow for our area. The NAM (which we are on the outskirts of its range) shows a unphased dual low scenario bringing rain showers to the area.

What else to note, the RPM model has shown this morning a significant snowfall (more so than the EURO) for the NJ area as well as New England. This is again another one of those things we will have to watch to see if this continues. All in all, there is more frozen precipitation on the table today as compared to yesterday.  There is a long way to go to bring frozen precipitation to our area. I am much more enthusiastic about this compared to yesterday. Finger crossed!

A Threat Looming?

A horrid winter trudges on for those loving snow. Each run of the models brings optimism and excitement, but this year usually leads to a let down. Rain  / snow line a bit west, north, temperatures a bit to warm, precipitation just not breaking out, the list continues.

Here we go once again. A lot of talks about a storm on Friday. The EURO had this for a number of consecutive runs (which usually means something). The GFS has now moved to the idea of a Noreaster taking shape on Friday. This does look to be a significant storm, and someone will get a lot of snow. Right now, my money is on New England. I will say this as well, the GFS has trended cooler each run which does mean, any cooler we too could be looking at snow here too. 

For now, a low pressure will phase with a northern stream disturbance off the coast of NC. From here, it will move up the east coast and come close to the "benchmark". The usual factors will need to be looked at here as always.....strong high pressure to the north, blocking, avail cold air, track, intensity etc. As for now, keep in your mind a storm is possible, with a lot of details to work out. 

Clipper Tonight, Bigger Storm End Of The Week

This week may well be remembered as one of the coldest over the past two years. This week will also be marked by bookend snow potential. A mild weekend has led way to crashing temperatures, snow chances and the lake effect snow machine cranking.

For our area, we are looking at a clipper moving through this evening. This will reinforce cold air, and bring us a chance at a period of snowy weather. This is not by any means, going to be a big event. In fact, this is going to resemble more along the lines of tracking a line of storms in the summer time. For those that see the squall move in, a quick burst of snow will cover the ground and could impair driving. A general coating to 1" can be expected.  Expect this to last less than an hour. The hi res NAM simulated radar has this over the area around 8pm tonight:

The real event for this storm tonight will be for areas in eastern New England (Boston to Portland, ME). They are going to experience what is known as a Norlun trough which will enhance the snowfall and really up totals in that area where 6" plus can be expected. I posted this a couple years ago when we had a Norlun trough move through our area, but here is the refresher for those interested:

                                                 Norlun Trough Explained (click link)

After this clipper moves through, our attention will turn towards Friday. Another storm is poised to move in and bring us a chance at some measurable snow fall. Weather models have been all over the place with this one, but the vast majority do show a storm. The next couple of days will be spent monitoring the weather models and trying to narrow down a consensus. We are looking at a Miller B storm, and historically, these are one of the most tricky storms to forecast. They can also lead to some of the most intense storms (a la our thunder snow storms for two winters ago.) For now, know that a chance exists and we will see how this plays out this week. Bundle up, going to be a cold one and hopefully snowy!